1. Field of the Invention
The present invention relates to aquariums and more particularly to an aquarium filter unit that includes different types of filter cartridges with each cartridge being replaceable.
2. Description of the Related Art
Aquarium filters utilizing filtering cartridges have long been known. At the present time, what is being manufactured and sold principally is an enclosed composite cartridge. Within that enclosed cartridge is located mechanical filtration, chemical filtration and sometimes biological filtration. The mechanical and chemical filtering cartridges are presently combined forming a composite cartridge. Almost invariably, the first stage of filtering that becomes ineffective is the mechanical filter. The mechanical filter is to filter out solid matter from the aquarium water. Typical solid matter would be feces and food particles. Once the mechanical filter becomes ineffective, the entire filter composite cartridge is to be discarded. The chemical filter and the biological filter within the cartridge in all likelihood will not require replacement. Even so, the cartridge is completely discarded. Within the United States alone, there are literally millions of aquariums. Millions of these composite plastic aquarium cartridges are being discarded and deposited in landfills which is really not necessary if only just the mechanical filter could be replaced. Also, aerobic bacterial cultivation takes place on the exterior surface of the activated carbon granules of the chemical filter and on the biological filter, and throwing out of the entire unit disrupts this cultivation. Not only is it wasteful for the aquarium hobbyist to dispose of filter cartridges that are not totally consumed, but it is also costly.